In an Long Term Evolution (LTE) system, a process of transmitting an uplink channel by a UE includes: the UE receives downlink scheduling signaling transmitted by a base station, demodulates the downlink scheduling signaling, prepares uplink data, allocates transmit power to an uplink channel according to obtained uplink channel information such as required power, or maximum transmit power allowed by the UE, and then transmits the uplink channel.
A subframe length may be 1 ms, and a Transmission Time Interval (TTI) length may be 1 ms. The scheduling may be performed by using a TTI as a minimum scheduling unit. To implement a shorter data transmission delay, a shorter TTI has been proposed. For example, the TTI length may be set to 0.5 ms or set to be shorter.
The UE may only support transmission of an uplink channel corresponding to a 1 ms TTI. After a short TTI (for example, a 0.5 ms TTI or a shorter TTI) is implemented, if the UE supports both a long TTI (for example, the 1 ms TTI) and the short TTI, it can be ensured that only an uplink channel corresponding to the long TTI is transmitted, and it may not be ensured that an uplink channel corresponding to the short TTI can also be transmitted. Therefore, it is needed to provide a solution in which the UE can transmit the uplink channel corresponding to the short TTI when supporting both the long TTI and the short TTI.